Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

Genetic deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and NADPH predispose affected erythrocytes to destruction from peroxides. Conversely, genetic deficiencies of catalase do not predispose affected erythrocytes to peroxide-induced destruction. These observations have served to strengthen the assumption that the NADPH/glutathione/glutathione peroxidase pathway is the principal means for disposal of H2O2 in human erythrocytes. Recently, however, mammalian catalase was found to have tightly bound NADPH and to require NADPH for the prevention and reversal of inactivation by its toxic substrate (H2O2). Since both catalase and the glutathione pathway are dependent on NADPH for function, this finding raises the possibility that both mechanisms destroy H2O2 in human erythrocytes. A comparison of normal and acatalasemic erythrocytes in the present study indicated that catalase accounts for more than half of the destruction of H2O2 when H2O2 is generated at a rate comparable to that which leads to hemolysis in G6PD- deficient erythrocytes.     

1141170685Tumor-infiltrating lymphocytes contain higher proportion of FOXP3+ T lymphocytes from cervical cancer than that from cervical intraepithelial zneoplasm

Ovine uterine serpin (OvUS) is the major progesterone-induced protein in the uterus of the pregnant sheep. This protein is a member of the serine proteinase inhibitor superfamily and it has been proposed to down-regulate uterine immune function during pregnancy to protect the fetus. In vitro experiments have shown that both the native and the recombinant (r) form of the protein can inhibit mitogen-induced lymphocyte proliferation and growth of canine primary osteogenic sarcoma cells, mouse lymphoma cells, human prostatic adenocarcinoma cells (PC-3 cell line) and bovine preimplantation embryos. The mechanism by which OvUS inhibits cell proliferation is still unknown. Accordingly, experiments were conducted to test whether rOvUS exerts its anti-proliferative action through apoptosis. In the first experiment, the anti-proliferative effect of rOvUS on PC-3 cells was tested to determine the minimal concentration effective at inhibiting proliferation. Proliferation was inhibited by concentrations of OvUS at 8 μg/mL and higher. The incorporation of [³H]thymidine was 4043, 3998, 3464, 2785, 2827, 2310, and 2332 dpm for 0, 0.5, 2, 8, 32, 125, and 250 μg/mL, respectively. In the second experiment, PC-3 cells were cultured for 48 hr with 50, 100 and 200 μg/mL of rOvUS or ovalbumin. Cells were then fixed and apoptotic cells identified using the TUNEL assay to detect DNA fragmentation. There was no effect of OvUS at any concentration tested on the percent of cells that were apoptotic. Percent apoptosis was 1.3% for control cells, 3.8%, 4.8% and 2% for cells cultured with 50, 100 and 200 μg/mL rOvUS, and 2% for cells cultured with 200 μg/mL ovalbumin. Results confirm that OvUS inhibits proliferation of PC-3 cells and indicate that inhibition does not involve induction of apoptosis. Further experiments are warranted to elucidate the anti-proliferative mechanism of action of OvUS.     

聚焦超声与低温等离子治疗后兔鼻黏膜形态学分析

目的 观察聚焦超声与低温等离子对鼻黏膜形态学的影响程度及意义.方法 运用聚焦超声技术,在设定的剂量参数下对兔鼻甲进行直线扫描;运用低温等离子射频消融术对兔鼻甲进行处理,在1个月及3个月后对两种方法处理后兔鼻甲切片及正常兔鼻甲切片进行对比观察,通过大体形态、光镜下观察对两种治疗方法兔鼻黏膜组织形态学的改变进行比较.结果 两种方法处理后1个月及3个月后兔鼻甲在外观和色泽无明显改变,光镜下显示兔鼻黏膜上皮层完整;运用低温等离子射频消融术处理后兔鼻甲外观较正常缩小,色泽灰白,且有分泌物存在,光镜下显示兔鼻黏膜上皮层断裂,部分切片上皮层完全消失.结论 在设定参数下聚焦超声可不破坏鼻黏膜上皮,可使鼻黏膜黏液纤毛系统功能得以完全保留.     

Cardiac Tamponade and Heart Failure Due to Myopericarditis as a Presentation of Infection with the Pandemic H1N1 2009 Influenza A Virus

We describe a fatal case of myopericarditis presenting with cardiac tamponade in a previously healthy 11-year-old child. Pandemic H1N1 2009 influenza A virus sequences were identified in throat and myocardial tissues and pericardial fluid, suggesting damage of myocardial cells directly caused by the virus.